This invention relates to a mounting mechanism for a ribbon cassette for removably mounting onto a printing station of a printer a ribbon cassette in which an ink ribbon is accommodated.
In a high grade printer, the operability in mounting and removing a ribbon cassette is considered important, and also a mounting mechanism for a ribbon cassette is complicated. However, in an inexpensive printer, thorough reduction in cost is required for every part.
FIG. 1 shows an exemplary one of conventional mounting mechanisms for a ribbon cassette. A pair of pins 2 are securely provided on the opposite sides of a ribbon cassette 1 while, on the side of a carrier or carriage 3 of a printer, a pair of recesses 6 for engaging with the pins 2 of such ribbon cassette 1 are formed on a carrier frame 4 and a pair of holders 5 which are supported for pivotal motion on the carrier frame 4 each by means of a pin 8. Each of the holders 5 is normally urged in the clockwise direction in FIG. 1 by a torsion spring 7.
When the ribbon cassette 1 is moved in the direction indicated by an arrow mark P, each of the holders 5 is pivoted a little in the counterclockwise direction in FIG. 1 against the corresponding torsion spring 7 by pushing of the corresponding pin 2 to allow the pin 2 to be fitted into the recess 6 formed on the carrier frame 4. After the pin 2 is fully fitted into the recess 6 of the carrier frame 4 in this manner, the holder 5 is pivoted back in the clockwise direction in FIG. 1 by the urging force of the torsion spring 7 until the recess 6 of the holder 5 presses against the pin 2 of the ribbon cassette 1 from above. Thus, the ribbon cassette 1 is mounted in position on the carrier 3 with the pins 2 thereof received in the recesses 6.
In such conventional mounting mechanism for a ribbon cassette as described above, the ribbon cassette 1 is simple in structure because only the pins 2 are provided thereon. However, there is a disadvantage that a considerable part cost and assembly cost are required because it is necessary to provide on the carrier side the holders 5 for receiving such pins 2 and the torsion springs 7 and pins 8 for the holders 5.